/*
Copyright 2020 The Knative Authors

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package v1

import (
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/runtime/schema"

	eventingduckv1 "knative.dev/eventing/pkg/apis/duck/v1"
	"knative.dev/pkg/apis"
	duckv1 "knative.dev/pkg/apis/duck/v1"
	"knative.dev/pkg/kmeta"
)

// +genclient
// +genreconciler:class=eventing.knative.dev/broker.class
// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

// Broker collects a pool of events that are consumable using Triggers. Brokers
// provide a well-known endpoint for event delivery that senders can use with
// minimal knowledge of the event routing strategy. Subscribers use Triggers to
// request delivery of events from a Broker's pool to a specific URL or
// Addressable endpoint.
type Broker struct {
	metav1.TypeMeta `json:",inline"`
	// +optional
	metav1.ObjectMeta `json:"metadata,omitempty"`

	// Spec defines the desired state of the Broker.
	Spec BrokerSpec `json:"spec,omitempty"`

	// Status represents the current state of the Broker. This data may be out of
	// date.
	// +optional
	Status BrokerStatus `json:"status,omitempty"`
}

var (
	// Check that Broker can be validated, can be defaulted, and has immutable fields.
	_ apis.Validatable = (*Broker)(nil)
	_ apis.Defaultable = (*Broker)(nil)

	// Check that Broker can return its spec untyped.
	_ apis.HasSpec = (*Broker)(nil)

	_ runtime.Object = (*Broker)(nil)

	// Check that we can create OwnerReferences to a Broker.
	_ kmeta.OwnerRefable = (*Broker)(nil)

	// Check that the type conforms to the duck Knative Resource shape.
	_ duckv1.KRShaped = (*Broker)(nil)
)

type BrokerSpec struct {
	// Config is a KReference to the configuration that specifies
	// configuration options for this Broker. For example, this could be
	// a pointer to a ConfigMap.
	// +optional
	Config *duckv1.KReference `json:"config,omitempty"`

	// Delivery is the delivery specification for Events within the Broker mesh.
	// This includes things like retries, DLQ, etc.
	// +optional
	Delivery *eventingduckv1.DeliverySpec `json:"delivery,omitempty"`
}

// BrokerStatus represents the current state of a Broker.
type BrokerStatus struct {
	// inherits duck/v1 Status, which currently provides:
	// * ObservedGeneration - the 'Generation' of the Broker that was last processed by the controller.
	// * Conditions - the latest available observations of a resource's current state.
	duckv1.Status `json:",inline"`

	// Broker is Addressable. It exposes the endpoint as an URI to get events
	// delivered into the Broker mesh.
	Address duckv1.Addressable `json:"address,omitempty"`
}

// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

// BrokerList is a collection of Brokers.
type BrokerList struct {
	metav1.TypeMeta `json:",inline"`
	// +optional
	metav1.ListMeta `json:"metadata,omitempty"`

	Items []Broker `json:"items"`
}

// GetGroupVersionKind returns GroupVersionKind for Brokers
func (t *Broker) GetGroupVersionKind() schema.GroupVersionKind {
	return SchemeGroupVersion.WithKind("Broker")
}

// GetUntypedSpec returns the spec of the Broker.
func (b *Broker) GetUntypedSpec() interface{} {
	return b.Spec
}

// GetStatus retrieves the status of the Broker. Implements the KRShaped interface.
func (t *Broker) GetStatus() *duckv1.Status {
	return &t.Status.Status
}
